New Method of Constant Pressure Water Supply System by Variable Voltage and Variable Frequency
变频调速恒压供水系统新方法

In view of the current most water-pump of the constant pressure water supply system running state single、and can not complete multiple pumps cycling work automatically,Thus to affect water-pumps used life and cause the problem which the resources are wasted,because of other water-pumps can not work for long time.This paper put forward to adopt LOGO! programmable controller which supports to use the graphical logical circuit to program,and according to the condition for increasing water-pumps and the condition for reducing water-pumps,the control functions of multi-pumps cycling automatically and switching pumps automatically in an assigned time are implemented.The Practical running result indicates that this method can effectively control the system,the system running has the stable reliability and perfect function.